Retarded alarm for connecters



A ril 9, 1929. R. TAYLOR I 1,703,244

RETAR'DED ALARM FOR CONNECTERS Filed Dec. 17, 1926 -5 E qinaId Zaylur W ill) Patented Apr. 9, 1929. i

UNITED STATES REGINALD TAYLOR, OF LIVERPOOL,

1,?68,Z PATENT OFFICE.

ENGLAND, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO ASSO CIA'IED TELEPHONE & TELEGRAPH COMPANY, OF KANSAS CITY, MISSOURI.

RETARDED ALARM FOR CONNECTERS.

Application filed December 17, 1926, Serial No. 155.473 and in Great Britain January 6, 1926'.

The present inventi m relate; to automatic or semi-automatic telephone .J tems and is more particularly coneerncd with test and supervisory arrangements for use in connection with final selectors as employed in such systems.

In cases where the release of the connection is under the control ol the alling party, it will generally happen that it the calling party delays to hang up at the end of a connection, since the connection will remain established to the called party. the latter will be unable to initiate a call himself in case he wishes to do so. Accordingly it is highly desirable, particularly in unattended exchanges, to make some provision for overcoming this dilliculty so that in case the c lling party, whether maliciously or otherwise, omits to replace his receiver in the usual manner at the t id of a conversation, the called party will not be inconycnicnccd.

Accori r to one feature of the invcnlion therefore. a system employing automatic switches in which the release ot. a connection is noinuilly controlled by the calling part y, means are provided for automatically eilectiing rclcase independently or" the calling party at ,r the called party has hung up.

According to another feature of the inven tion in :1. system employing automatic switches the release of which is normally cont rolled by the calling party. timing apparatus connnou lo a number of battery-feeding switches is iulllpl'ttl to etlect the release ol' an operated switch a in'edetermined time after the called party hangs up. It usually desirable that the apparatus provided for producing these ell ecl's shall be common to a number of switches and it is then important to arrange that the client oi successive overlapping calls from different: switches shall not be cumulative so as to cllccl a premature release belorc the predetcrmined time period has expired. This also is taken care of according to the invention by the provision ot a. hunting switch for a-zso-ciating the common apparatus with only one switch at a time and by arrangiiu: that the common apparatus must be restored to normal between successive associations with different switches.

The above features will be better appreciated from the following description of one method of carrying the invention into ellcct, which is illustrated in the accompanying drawing. It will be uiulerstood however, that this arrangement is given by way of example only and that various moditications of it could be dc ised without exceeding the scope of the invention.

Referring now to the drawing, this shows in the usual manner the circuits of a connecter or final selector of well known type together with the alarm and supervisory equipment which is common to a number of conncctcrs depending on the capacity of the rotary switch.

in order that the complete operation of the apparatus show u may be properly understood. a brief description will first be given or the changes which take place when the connector is used for extending a connection to a wanted line, though since the normal o erating circuits of this switch are well lanown and form no part of the inven ion, they will not be described in full delzil. Vhen the switch is taken into use from a. preceding selector, line relay A operates and completes a circuit for release relay ll, which prepares the switch for operation and supplies earth to the release trunk conductor to hold up the preceding switchcs. The calling party then dials the next digit in the antcd number whereupon relay A dcenergizes correspondingly and impulses are sent to the vertical magnet to step the switch up to the required level. Relay C. which is slow. is operated throughout the train of im pulses and when they terminate it releases and connects the operating circuit through to the rot .ry magnet. This magnet is accordingly operated in resptmse to the next and last train of impulses and thereupon rotates the wipers into engagement with the contacts of the desired line. Relay l) is operated throughout this train of impulses and serves to delay the testing operation um til the wipers have come to rest. lri ca e the wanted line is busy. relax (t then cp crates to prevent the connection being switched through. and to give busy tone to the ca ling party. while it the line is free. relay H operates in series with the cut-oil relay of the wanted partys line switch and connects up the line wipers and starts the ringing. Vhen the wanted party replies. the ring-cut-ofl' relay F operates to disconnect ringing current and complete the speaking connection and remains locked up to lit) iii)

the release trunk conductor. The backhridge relay D is then operated over the wanted partys loop and in the arrangementshown reverses current flow back over the connection for supervisory or metering purposes.

The circuits remain in this condition while the conversation is in progress, and when the calling party hangs up, relay A deenergizes and opens the circuit of relay B and when this relay releases earth is removed from the release trunk conductor 9 whereupon all the preceding switcaes are released in known manner. Moreover a circuit is also completed orer the oft-normal contacts for the release magnet Z of the connecter which ope ates to restore the switch to normal. In case however the calling party should delay to hang, up, the connecter would remain in its ope 'ated position and the eltect of replacing the receiver at the *alled substation would be merely to deenergize relay 1); then in case the called party wished to initiate a connection himself while the connectcr was still in operated position, he would be unable to do so as the only effect produced when he removed his receiver again would be the re-energization of relay I). Owing to the delayed release feature about to be described lo vever, this state of affairs will not persist indefinitely and after a short interval the switch will be released and preferably a. alarm will be given to notify an attendant; this operation will now he described in more detail.

It will he seen that under the conditions which it is desired to guard against, relay 1 will be. operated but relay 1) will be deenern'ized. In these circumstances a circuit completed as follows: battery, lamp LP, (which individual to the connectcr shown), armature l3 and its front contact, armature It and its back contact, common lead 20, back contact and armature l2. winding of relay 1A to earth. Relay L thereupon operates and at armature 2t completes a circuit which extends over armature 2:2 and its incl: contact, hack contact and armature -13. interrupter con act and winding ot magnet D to bat ery. The wipers lt3 of the rotary switch are therefore set. in operation and as soon as wiper 1 leaves its normal contact. earth is connected over the bank of this wiper to maintain a circuit tor the magnet so that the switch cont hates to operate. even in case relay IA should be deencrgized at this time. The advance of the i ipers continues until they engage the contacts associated with the connecter which is being held. whereupon wiper 2 encounters earth, and a circuit is completed from the release trunk conductor 9. front contact and armature 12. back contact and armature 10. contact in the bank of wiper 2 and said wiper, back contact and armature 41, upper CO to battery. Relay CO winding: of relay is thercu on operated and at armature opens the *ircuit of the magnet D so to bring the switch to rest; at armature 24: completes a direct circuit to earth for the lamp LP, at the same time shorting out relay L; at arn'iatnres and 25 connects up the clock contacts CG so that impulses a sent to the chain 0t relays 2T 32 and at armature 26 prepares locking circuits tor these relays.

It should be mentioned at this point that the arrangement of the circuits permits a connector to be rached over the normal contacts ot the rotary switch, as shown, and in this case the relay L does not actually operate since a circuit is at once completed for relay ((3 and the magnet circuit opened hetore the wipers have been moved. The more gen ral case has been described above however it. order to give a fuller understanding of the circuits.

The clock conla CC are cmiveniently closed every halt minute and upon the first closure after the operation of relay CO, a circuit is cmnpleted for two-step relay 2? which thereupon operates its light armature i so as to connect up its lower winding. \Yhen contacts CC open. the short-circuit round this winding: is removed and the relay operates tally and at armature 2-7-5 transthe circuit from the contacts CC to the next chain relay Since six chain relays are provided. it will be tl TpitCitltttl that at'ter the lapse of a three-minute interval, it' the conditions still persist, the last, relay I132 will ated and this in addition to lockingin U ,i nature 526 as u iiza, at armature 37 completes a circuit over lead 38 for an alarm. at. armature 35 comple es an additional circuit over the lower winding of reloy Ct which circuit extends orer wiper l to the release trunk conductor 9. and at armature 3i") completes a circuit which extends over wiper El and the otl normal contacts of the connecter to release ni-i na whereupon the rel ase magnet ope-ales and the switch is restored to norm: in cureducnce ol' the release oil the switch, the called party is no longer prevented from extend a call but in the ar a nrement shown the train of witches st ll remains set p until the attendant. who has men notilied the alarm. takes steps to release them. in order to locate the switch which has initiated the alarnn he has only to look tor the lamp LP which is, li 'hterl. \Yhen the switch train is tinally cl ired down and earth is removed them the relea:- e trunlr. conductor 9. relay (0 tie-energizes and a homing); circui' then completed from earth, wiper 1 t e homing he 1k. armature 22 and ts ntact. ha k contact and armature 43, nterrupter con act and winding; of magnet; D to battery, so that the switch. is

fl t) iii) Iii)

restored to normal in readiness tor reoperation in the case of another blocked call. It will be appreciated that in case the calling party hangs up before the three-minute interval has expired, the circuit through the upper winding; ot the relay CO will be opened and such of the chain relays as have operated will be released so that there is no danger of the ettect being cumulative in case another call requiring attention should occur on some other connector immediately.

It will be apparent to those skilled in the art that though the arrangement shown is only adapted to etlcct the release of the connector while keeping: the remainder ot' the switch train set up, there would be no particular difliculty in arranging' for the whole connection to be released by the removal of earth from the release trunk conductor. For instance, the earth extended over wiper 2 might be arranged to operate a slow release relay which opened the circuit of relay A and thus ctlected the release of relay ll also, and hence the conn 'iletion ot the release magnet circuit. It will he apprcciated also that in case the battery feedin was from the first switch in the train rather than the last, the common equipment would for the sake of convenience preferably be associated with this first switch, though clearly also the called partys line would be :l'reed it only the connecter switch were released.

A brief description will now be given of the sequence of operations in case the equipment shown is to be used tor GIIGtti] '2; rontingr tests. In this case a test plug inserted in the jack J and a circuit is then completed for the operation of relay S. This relay thereiu'ion at armature ll disconnects the relay CO, at armat are 42 disconnects the relay L. and at armature 43 chang jes over the circuit tor the rotanv magnet I) so that it may be controlled hy ray of the test plug. It will be seen that a circuit con'iplet d tor the magnet I) over wiper at as lone as this wiper engages contacts a sociatcd with connecters which are in use, as indicated by the presence of earth on the release trunk corductor. The wipers ot the switch th refore continue to rotate until they are moved into engagement with a tree connectcr and the hey K in the testing c piipnicnt is then thrown. whereupon a circuit is completed through the dial springs llti, ovcr wipers 5 and (S and by way of line conductors T and 8 for the line relay A. This accordingly operates in the usual manner and completes a circuit tor relay B, upon the operation of which earth connected to the release trunk conductor to busy this connecter to selectors having access to it. The operation ot the key K also opens the original circuit for the magnet D so that when this earth is extended back to wiper 4, the magnet shall not again operate. The attendant now llltllllllll lates the dial as desired, for instance in accordance with the test number, whereupon the impulses produced at the springs D8 are etlective for setting the connecter switch in the same way as under the control of a calling subscriber. When the attendant has ascertained that the switch has operated satisfactorily, he will restore the key K therehy opei'iing the circuit for the line relay A which will release and open the circuit of relay 1). \Vhen both these relays have fallen away a circuit will be completed for the release mag'net and the switch will be restored to normal as usual. In the I eantime, the completion of the circuit for the magnet I) at the lower springs of the key K will cause the rotary switch to hunt for the next tree, connecter upon which the same test may then be made. In case the switch has not returned to normal when the attendant withdraws the plug from the jack J, this will be taken care of when relay S de-energizes since the usual homing: circuit is then completed over wiper 1.

What is claimed is:

1. In an automatic telephone system wherein connections between called and calling lines are made by means including a *onnecter, and wherein the connector is aranged so that it may lie n'iaintained in an operated position when the called par y terminates the call, a device operated responsive to the termination of a call by the called party to hunt for the connccter, a signal in dividnal to the conne er operated wl-en the connector is found, and a signal in the device operated within a prtwlcternlined period ot time,

2. In an automatic telephone system wherein connections between called and calling lines are made by means including}; a connecter. and wherein the connector is arranged so that it may be main ained in its operated position when the called p rt y terminates the call. a device operated responsive to the termination of a call by the called party to hunt for the connecler, a signal individual to the eonnecter operated when the connecter is found. and means operated a n'edctermintal period oi" timc thereafter to release the connecter.

3. In a telephone system wherein a corn ncctcr is directly controlled by the calling party to establish connections to a desired line and wherein the connecter is released resp msi\.'e to the termination of the call by the calling party, a connecter rclcar-aine device, and means in said device operated a predetermined period o'l time after the called party has terminated the call to cause the release of the connecter.

at. In an automatic telephone system wherein connections between called and calling lines are made by means of switches 'including a l'zizal connector, and wherein the connecter arranged so that it may he maintained in its operated poeition when the called party terminates the fall, a time lneaquring device initiated in its operation respi'ineive to the termination of a all by the called party illQfiliiS for releasing both said device and the Switches including the erter when the calling party terminates ca l, and insane oper'ited by the time llltfttfilli'l i device it it not rel used within a predete mined period of time to cau e the relezwe ot the c nnecter .vhile maintaining the other switchea operated.

In a telephone hffhttlll wherein a connecter if; Ieed to establish connection to a desired line and wherein the connector is; released re:'- pone ive to the termination ot the call by the calling: party. a deiiee tor ineur the, release of the connerter Within a predeterinined period of time after the railed party teriniuatea the call, a Signal individual to the d vice to indicate that the device has operated to cause the l' ilttlflij ot a eoiuiecter. and a ie'nal individual to the conuecter to indicate that it has been releaaed by said device.

(3. in a telephone system wherein a C01- nect'er is 11 ;Qil to establish connections to z def ired line and wherein the connector released reqmnezive t0 the termination o the call by the calling: party, a device for insuring the releaee ot' the c uecter Wii" in a i redeterinined p riod ot tn at'ter the l' terminates the call, mean, to:

iizrg the device ineffective for jilliPHl-Tta and t1 cauaing'said device to a: tomaticallv hu tor an idle conreeter, us; tor teetingj the connecter over said device, and nieansi reaponeive to the termination ot' the test to cause the device to hunt for a lifferent coiuuicter.

7. In C(llillil} tiOEL a hunting; device. a plurality of connect ZlCf'ttwbllllO thereto is found, manually operated means for preventing that hunting movement of the device and for iauaing the device to automatically hunt for and select an idle connocter, means for testing the selected counecter, and means responsive to the termination oi the test to cause the device to hunt for a different idle connecter.

8.1:: combination a hunting device, a )lurality of conneeters accessible thereto, neans for automatically starting Said device hunting); for a connecter over which it called party has terminated a call While the calling); party is attempt ng to continue the call. a signal operated when the connecter found manually operated means for pre venting that hunting movement of the dc vice and for causing the device to automatically hunt for and select an idle conneeter, means for testing: the selected (oi necten means reaponnive to the termination of the test to cause, the device to hunt, for a difl'eren idle ronnecter, and connections etl'ective when the manually operated means released to cause the return of the device to its normal position.

9. In a telephone v yssten1 the combination with a connecteiu of a device for inauringr the release of the conneeter Within a predetermined period of time after the called party terminates :1 call, and means in the, device for converting it into a eonnecter testing zmparatua.

it(). in :i tPlOPl'IN-JP s ve iern a testing dea plurality ol connecters accessible ther tzn means: for causing the device to j ically hunt for and Ftlt l' an idle wanecter, a key in Said device for selzing or releasing the selected connector, means in the levice for toiling the seized con-"ieeter ii a desired nninneix and UMEEYW reeponsive o the r-iease operation of the k v to cause:

to nnnt 101' REGINALD TAYLOR.

till 

